A/C Clutch Mode

Range Clutch Enab. Reg/A/C Reg. Off/Off, Low Voltage/ Off, High Temperature/Off, High Pressure/Off, Low Ambient/Off, Low RPM:

The message displayed refers to the class 2 serial data communication message from the PCM to the BCM. This message monitors the current state of the A/C compressor clutch. The PCM performs the following functions:
^ Prevents compressor overspeed
^ Limits compressor speed (park and neutral) detect defective
^ Detects a defective transducer
^ Drives the compressor clutch
^ Performs anti slug

The BCM performs the following functions:
^ Limits the low speed compressor operation
^ Prevents clutch slippage (monitor voltage)
^ Monitors for high coolant temperature
^ Monitors for overpressure
^ Determines low ambient pressure
^ Controls the compressor clutch

The Clutch Enab. Req (Clutch Enable Requested) display indicates that the PCM is driving the A/C clutch. The A/C Req Off (A/C Requested Off) display indicates that the PCM is not driving the A/C clutch. The off, low voltage display indicates that the PCM is not driving the A/C clutch because of low battery voltage (10 Volts or less). The off, high temperature display indicates that the PCM is not driving the A/C clutch because of high engine coolant temperature above 121°C (250F).

The off, high pressure display indicates that the PCM is not driving the A/C clutch because of high A/C compressor outlet pressure (above 2928 kPa (424 psi). The off, low ambient indicates that the PCM is not driving the A/C clutch because of low ambient pressure (below 227 kPa (33 psi). The off, low RPM display indicates that the PCM is not driving the A/C clutch because of low engine RPM (4 cylinder below 465 RPM, 6 cylinder below 440 RPM).